Fuel pump



Feb. 27, 1962 c. H. TUCKEY 3,022,737

FUEL PUMP Filed May 6, 1959 WAV/1471;,

lll/14111 INVENToR. I/

cfm/a4 fs ff. rackyfr BY A ATTORNEYS United States Patent Charles H.Tucirey, Sass tCity, Mich., assigner 'te Waihro Corporation, Cass City,Mich., a corporation or Michigan Filed May 6, i959, Ser. No. SlLil'! 2Claims. (Cl. 10S-nda) This invention relates to a fuel pump and isparticularly intended to be an improvement on cca-pending application,Serial No. 766,614, iled Gctober l0, 1958, new Patent No. 2,984,188.

It is an object of the present invention to provide a construction whichis relatively simple and economical as far as the manufacture isconcerned and one in which there are no mechanical parts which can wearout or become mechanically out of order.

Another object of the invention is the provision of a housing whichadapts to a very simple valve construction for a fuel line pump.

Other objects and features of the invention relating to details ofconstruction and operation will be apparent in the following descriptionand claims.

Drawings accompany the disclosure and the various views thereof may bebrieily described as:

FIGURE l, a sectional view showing the relationship of the parts of thepump.

FIGURE 2, a sectional view on line 22 of FIG. l.

FIGURE 3, a modied view of the construction showing the manner in whichthe housing can be used as a lilter.

Referring to 'the drawings, in FIGURE l, a main housing 10 has a sideextension l?. tapped to receive a nipple connection la. Fl`he housinghas a central bore forming an elongate chamber i6 and a concentricannular recess 1S around the central bore. At the bottom of the housingis a hose connector projection 2t) opening into the central bore 16. Atthe bottom of the central bore is a conical valve seat 22.

Disposed within the central bore is a sac diaphragm 24 having a radial,outwardly extending, sealing ilange 26 extending outwardly over therecess l. The closed end of the sac 24 contacts and seals the valve seat22 as a unidirectional valve admitting fuel from a supply. The sac alsodivides elongate chamber le into a fuel re' ceiving chamber outside thesac and a 'pulsation pressure chamber inside the sac.

A cap 30 is pressed over a slight annular ridge 28 on to the open end ofthe housing liti and serves to clamp the sealing ange Z6 over the top ofthe housing. The cap 30 has a hollow hose connection 32 which is adaptedto be connected to a source of pulsating pressure such as a crank caseof a two-cycle engine or a manifold or a carburetor passage. The hollowprojection Z serves as an inlet for a fuel supply and the nipple 14serves as an outlet. In the wall between the bore 16 and the recess 18is an opening 34 which is closed by a wide rubber band or cylinder 36.This hole 34 is aligned with a second hole 33 leading to the nipple lid.

in the operation, pulsating pressure in the main bore inside the sac 2liwill cause the sac to enlarge and ensmall, thus reducing the pressure inpassage lil and also causing the sac which contacts the valve seat 22 torefrom the valve seat. T his carries fuel into the bore l outside thesac 2d. Ile-expansion of the sac 24 again seals the valve seat 22 andforces liquid out through hole past the elastic band 36 into the outletpassage 38. rhere is thus provided an extremely simple pump constructionwhich has no mechanical parts.

In FIGURE 3 a modified construction is shown using the same housing butusing a closed cap Sil with an annular seal ring 52. The cap Sil has anannular recess 54 which receives one end of a cylindrical screen elementSe, the other end of which bears against the bottom of bore le. Also inthe cap is a depending magnetic element SS which projects into the areainside the screen 56. ln the operation of the device flow will enter thepassage di), pass through the screen and out the openings 3dand 38. Anymetal particles in the gas will be attracted to the magnetic element 5?to keep them out of nui.

the engine. The cap may be removed and the element 56 cleaned orreplaced.

l claim:

l. A fuel pump for small engines to operate `from a source o pulsatingpressure in the engine of the type having a housing with a pumpingchamber, an inlet and an outlet to said opening, an inlet valve andadiaphragm Within said chamber, that improvement which comprises a meansforming an annular chamber around said pumping chamber, a passagethrough the Wall of said pumping chamber connecting to said annularchamber, said annular chamber being connected with the outlet of saidpump, and an outlet valve comprising a band of resilient mate# rialpositioned snugly around the inner walls of the annular chamberoverlying the connection with said pumping chamber, said materialpermitting ilow outward from said pumping chamber into said annularchamber and blocking ilow in a reverse direction.

2. A pumping device as defined in claim 1 in which the pumping chamberand the annular chamber are opened at one end of the housing, and meansclosing the open ends of said chambers at said end of said housing forconnecting said pumping velement to a source of pulsating pressure.

References Cited in the tile of this patent UNITED STATES PATENTS1,503,279 NiXOn July 29, 1924 2,920,573 Schaurte Ian. l2, 1960 FOREIGNPATENTS 79,747 Netherlands Nov. 15, 1955 257,519 Italy Mar. 7, 1928

